fig01: Capn4 expression in nasopharyngeal carcinoma (NPC)biopsy tissues and cell lines. (a) mRNA levels of Capn4 in tumor tissues from seven patients with NPC and two normal tissues were determined by RT-PCR. The results were normalized against mRNA levels of β-actin in each sample. N, normal tissues; T, tumor tissues. (b) Western blot analysis on Capn4 expression was performed in NPC tumor tissue samples and normal tissues. Total proteins were extracted from tissues and subjected to immunoblotting probed by antibodies against Capn4. β-actin was probed as control. (c, d) Capn4 mRNA and protein levels were monitored in the NPC cell lines (5-8F, CNE2, and 6-10B) and the immortalized human nasopharyngeal epithelial cell line NP69, respectively. *P < 0.05.

Mentions:
To examine expression of Capn4 in primary NPC tumor and normal nasopharyngeal tissues, RT-PCR and Western blot analysis were performed to detect mRNA and protein levels. The results revealed that the Capn4 mRNA and protein expression level was significantly upregulated in NPC tissues (n = 7) compared with normal nasopharyngeal tissues (n = 2; Fig.1a,b). In parallel, upregulation of Capn4 was also observed in three NPC cell lines, 5-8F, CNE2, and 6-10B, when compared to immortalized normal human nasopharyngeal epithelial cell lines NP69 (Fig.1c,d).

fig01: Capn4 expression in nasopharyngeal carcinoma (NPC)biopsy tissues and cell lines. (a) mRNA levels of Capn4 in tumor tissues from seven patients with NPC and two normal tissues were determined by RT-PCR. The results were normalized against mRNA levels of β-actin in each sample. N, normal tissues; T, tumor tissues. (b) Western blot analysis on Capn4 expression was performed in NPC tumor tissue samples and normal tissues. Total proteins were extracted from tissues and subjected to immunoblotting probed by antibodies against Capn4. β-actin was probed as control. (c, d) Capn4 mRNA and protein levels were monitored in the NPC cell lines (5-8F, CNE2, and 6-10B) and the immortalized human nasopharyngeal epithelial cell line NP69, respectively. *P < 0.05.

Mentions:
To examine expression of Capn4 in primary NPC tumor and normal nasopharyngeal tissues, RT-PCR and Western blot analysis were performed to detect mRNA and protein levels. The results revealed that the Capn4 mRNA and protein expression level was significantly upregulated in NPC tissues (n = 7) compared with normal nasopharyngeal tissues (n = 2; Fig.1a,b). In parallel, upregulation of Capn4 was also observed in three NPC cell lines, 5-8F, CNE2, and 6-10B, when compared to immortalized normal human nasopharyngeal epithelial cell lines NP69 (Fig.1c,d).

Bottom Line:
The patients with NPC displaying higher Capn4 had a significantly shorter overall survival (P = 0.002) and progression-free survival (P = 0.003).These events resulted from Capn4 downregulation were associated with reduced expression of matrix metalloproteinase 2 (MMP2), Snail, and Vimentin.Together, these findings argue a novel function of Capn4 in invasion and metastasis of NPC, and thereby suggest that Capn4 may represent an independent prognostic factor and a potential therapeutic target in NPC.